EP1047567A1 - Tyre bead with reinforcing circumferential elements - Google Patents

Tyre bead with reinforcing circumferential elements

Info

Publication number
EP1047567A1
EP1047567A1 EP98966633A EP98966633A EP1047567A1 EP 1047567 A1 EP1047567 A1 EP 1047567A1 EP 98966633 A EP98966633 A EP 98966633A EP 98966633 A EP98966633 A EP 98966633A EP 1047567 A1 EP1047567 A1 EP 1047567A1
Authority
EP
European Patent Office
Prior art keywords
reinforcement
ply
bead
radially
point
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP98966633A
Other languages
German (de)
French (fr)
Other versions
EP1047567B1 (en
Inventor
Pascal Auxerre
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Compagnie Generale des Etablissements Michelin SCA
Original Assignee
Compagnie Generale des Etablissements Michelin SCA
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Compagnie Generale des Etablissements Michelin SCA filed Critical Compagnie Generale des Etablissements Michelin SCA
Publication of EP1047567A1 publication Critical patent/EP1047567A1/en
Application granted granted Critical
Publication of EP1047567B1 publication Critical patent/EP1047567B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
    • B60C15/00—Tyre beads, e.g. ply turn-up or overlap
    • B60C15/06—Flipper strips, fillers, or chafing strips and reinforcing layers for the construction of the bead
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
    • B60C3/00—Tyres characterised by the transverse section
    • B60C3/04—Tyres characterised by the transverse section characterised by the relative dimensions of the section, e.g. low profile
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T152/00—Resilient tires and wheels
    • Y10T152/10—Tires, resilient
    • Y10T152/10495—Pneumatic tire or inner tube
    • Y10T152/10819—Characterized by the structure of the bead portion of the tire
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T152/00—Resilient tires and wheels
    • Y10T152/10—Tires, resilient
    • Y10T152/10495—Pneumatic tire or inner tube
    • Y10T152/10819—Characterized by the structure of the bead portion of the tire
    • Y10T152/10828—Chafer or sealing strips

Definitions

  • the present invention relates to a tire with a radial carcass reinforcement intended to carry heavy loads, and more particularly to a tire of the "Heavy Duty" type, intended to equip vehicles such as, for example, trucks, road tractors, buses, trailers and others, and more particularly the new reinforcement structure of the beads of said tire-
  • a tire of the type under consideration comprises a carcass reinforcement formed of at least one ply of metal cables, anchored in each bead to at least one bead, by forming a reversal.
  • the carcass reinforcement is radially surmounted by a crown reinforcement, composed of at least two plies of metal cables, crossed from one ply to the next, forming angles of between 10 ° and 45 ° with the circumferential direction.
  • Carcass reinforcement upturns are generally reinforced by at least one bead reinforcement ply formed of metal cables oriented at a small angle relative to the circumferential direction, generally between 10 ° and 30 °.
  • the latter In the case of the presence of a single bead reinforcement ply, the latter is generally located axially on the outside, along the carcass reinforcement upturn, with a radially upper end situated above or below the radially upper end of the carcass reinforcement upturn. As for the radially lower end of such a reinforcement ply, it is generally located on a straight line parallel to the axis of rotation and passing approximately through the center of gravity of the meridian section of the carcass reinforcement anchor rod.
  • the known solution aims to avoid deradialization of the cables of the carcass reinforcement upturn, as well as to minimize the radial and circumferential deformations undergone by the end of said upturn, and by the outer rubber layer covering the bead and ensuring the connection with the rim.
  • the carcass reinforcement of a radial tire mounted on its service rim and inflated to the recommended pressure, has in a sidewall a regularly convex meridian profile between approximately the zones of connection with the meridian profile of reinforcement of apex and with the bead.
  • said reinforcement has a substantially rectilinear meridian profile or even curved in the opposite direction to the curvature in the sidewalls, that is to say substantially parallel to the curvature of the rim flanges from an inflection point located radially approximately at the radially upper end of the bead reinforcement ply, placed along the carcass reinforcement reversal.
  • Such an architecture leads to relatively thick beads of tires.
  • said tire comprises at least one radial carcass reinforcement, formed of at least one ply of inextensible reinforcing elements and anchored in each bead B to at least one rod to form a reversal, each bead B being reinforced by an additional reinforcement frame formed of metallic elements.
  • the carcass reinforcement has a meridian profile, the layout of which, between point A of greatest axial width and the first point of tangency T with the coating layer almost circular of the anchor rod, is convex over its entire length, and such that the thickness ⁇ of the bead B, measured on a perpendicular to said meridian profile at a point C of height hc, between 30 and 40 mm and measured by relative to the bead base Y Y ', ie between 2.5 and 3.0 times the thickness e of the flank measured on the right D "line of greatest axial width, said carcass reinforcement being reinforced, in its non-turned part , through additional reinforcing reinforcement formed of at least one ply of circumferential reinforcing elements disposed axially inside said non-turned part.
  • the point A of greater axial width is, by definition, the point of the meridian profile of carcass reinforcement corresponding to the point of greater axial width of carcass reinforcement when the tire is mounted on its service rim and inflated to the recommended pressure and not loaded, and the straight line D "of greatest axial width is the straight line parallel to the axis of rotation and passing through A.
  • the additional reinforcing reinforcement elements are said to be circumferential if the angle they form with the circumferential direction is between + 5 ° and - 5 °.
  • the convex line of the meridian profile of the carcass reinforcement is generally formed by several adjacent arcs of circle, the radii of curvature of which increase from the point A of greatest axial width to the point of tangency T with the coating layer.
  • the ply (s) of the additional reinforcement armature, axially inside the non-turned part of the carcass reinforcement, will advantageously have their ends radially lower radially below the straight line D ', parallel to the axis of rotation and passing through the point of the coating layer of the anchor rod radially furthest from the axis of rotation, but above the straight line D, parallel to the axis of rotation and passing through the point of the coating layer of the anchor rod radially closest to the axis of rotation, and radially upper ends situated at a radial distance from the straight line D, between an amount equal to the radial half-distance between the straight lines D and D "increased by the radial half-distance between the lines D and D ', and an amount equal to the radial half-distance between the lines D and D "minus the radial half-distance between the lines D and D'.
  • This structure thus allows a partial recovery of the meridian tension forces undergone by carcass reinforcement, and thus minimizes the radial deformations at the ends of the carcass reinforcement upturn, whatever the driving conditions.
  • reinforcing elements of additional reinforcement will be more numerous; they will preferably be metallic, steel, mutually parallel in the additional ply and joined over the entire width of the reinforcing reinforcement.
  • Reinforcement elements are said to be contiguous if, in the direction perpendicular to said elements, the distance separating two adjacent elements is reduced to the maximum.
  • Patent FR 750 726 of the applicant teaches the bonding of carcass reinforcement plies to auxiliary reinforcements, each formed from wire wound in a spiral and having consequently a notable flexibility in the transverse direction. Said bonding is carried out so that two carcass reinforcement plies enclose an auxiliary reinforcement, said clamping being effected in the absence of rod and carcass reinforcement flipping.
  • Patent FR 1,169,474 also teaches to remove the rod usually used by small plies of metal wires or cables inclined on the attachment parallel, the angle of inclination being able to descend to 5 °, the ply (s) (s) of carcass reinforcement being returned or not.
  • Patent FR 1 234 995 provides for the replacement of the usually oblique reinforcement elements of the bead reinforcement ply (s) intended to reduce the movements of the attachment against the rim flange, by circumferential elements. , reinforcing reinforcement which can be arranged between the main part of the carcass reinforcement and the reversal of said reinforcement, or axially outside said carcass reinforcement reversal.
  • Document FR 2 055 988 describes a certain number of possible applications of a reinforcement of a bead with elements circumferential, in particular the use of such a reinforcement instead of the usual reinforcement with oblique elements arranged axially outside the carcass reinforcement upturn.
  • the above rod types allow less space due to the shape of their cross section, but also because the resumption of forces by additional reinforcement allows a significant reduction of said sections.
  • the cross section can be reduced by 30 to 50%, which leads, compared to the application of the invention, in the case of a rod with more bulky rectangular wires, to have either a more thinned bead thickness, or a constant bead thickness but with a so-called tauter meridian profile, in the sense that its convexity is less pronounced.
  • the bead reinforcement thus described can be produced separately by spiral winding on a horizontal support of suitable shape, and then transferred to the unvulcanized tire blank.
  • At least one ply formed of metallic elements is present in the additional reinforcement frame.
  • Said additional ply, axially on the outside, will have its radially upper end situated radially in the same way as the ply (s) axially on the inside, while the radially lower end of this second ply will advantageously be located between the right From and a parallel line à D 'radially outside and radially distant from D' by an amount equal to the radial distance separating D 'from D.
  • the reinforcing elements of said second ply will preferably be sections or set of sections of steel wire cables of circumferential length at most equal to 0.4 times the average circumferential length of the reinforcing reinforcement thus formed.
  • FIG. 1 schematically represents, seen in cross section, a tire structure, known from the state of the art
  • FIG. 2 schematically represents an enlarged view of a first variant of bead according to the invention, in its most stripped down version
  • FIG. 3 shows schematically a second variant of bead according to the invention, the rod being a braided rod, and with a reinforcement of bead reinforcement with two plies.
  • the tire P shown in FIG. 1 is a tire of dimension 315/80 R 22.5, intended to be mounted on a rim comprising rim seats inclined at 15 °.
  • Said tire comprises a tread (4) joined to two beads B by means of two sidewalls (5).
  • Each bead B is reinforced by a rod (1) formed by winding on a suitable form a wire with a quadrilateral section until several rows of radially juxtaposed wires are obtained.
  • a carcass reinforcement (2) composed of a single ply of metal cables.
  • the anchoring is done by a reversal (20) around the layer (10) of rubber mixture which covers the rod (1), the radial distance h, separating the radially upper end of said reversal (20) from the straight line YY ' parallel to the axis of rotation and defining the nominal diameter of the bead (which is the same, in the case described, as the diameter of the service rim), being equal, in the example studied of the tire of dimension 315/80 R 22.5, at 37 mm.
  • a rod stuffing (71) in a rubber mixture of generally high Shore hardness.
  • a reinforcement ply (6) formed of inextensible metallic cables weakly oriented relative to the circumferential direction, and the radially upper end of which is further from the axis of rotation. that the upper end of the carcass reinforcement upturn (20) (2).
  • Said ply (6) is separated from the rod stuffing (71) by a second filling stuffing (72), and from the protective rubber mixture (8), which surrounds the bead B, by a rubber mixture profile (73).
  • the bead B of the tire of the same dimension, in accordance with the invention and shown in FIG. 2, is, in an identical manner, reinforced by a bead wire (1) with rectangular wires, and surrounded by a layer (10) of rubber mixture. with a high elongation module, around which is anchored carcass reinforcement (2) to form an upturn (20).
  • Said bead B has the following two essential characteristics in combination: the carcass reinforcement (2) has, seen in meridian section, a meridian profile, between point A of greater axial width and the first point of tangency T of said profile with the quasi-circular coating layer (10) of the rod (1), which is continuously convex, and the bead reinforcement reinforcement (6), composed, in the example described, of a single ply (6) of circumferential elements, is placed axially inside the non-turned part of the carcass reinforcement (2) and not axially outside the reversal (20) of the carcass reinforcement (2).
  • the convexity of the meridian profile allows, compared to the tire of the prior art with a profile tracing passing from convex to concave, allows a non-negligible thinning of the bead B.
  • the bead in accordance with the invention, has a thickness equal to 2.9 times the thickness e of the sidewall, measured on the straight line D "parallel to the axis of rotation and of greater axial width, while the bead B of the tire of FIG. 1 has a thickness, measured under the same conditions, equal to 3.4 times the thickness e. Said thinning, visualized in FIG.
  • the bead B is reinforced by at least one additional reinforcement ply (61) of upper elements modulus of elasticity and arranged circumferentially, said ply (61) being located axially inside the carcass reinforcement (2) whose meridian profile is convex.
  • the reinforcing elements of the ply (61) are sections of 27 x 23 metallic cables, the length of said elements or sections of cables being equal to a quarter of the circumferential length of said ply (61) measured when it is laid on the drum for making the carcass reinforcement blank.
  • the spaces between the ends of the elements are of small amplitude: 3 mm (also measured during installation) and are offset circumferentially between them.
  • the radially lower end of the ply (61) is substantially disposed on a straight line parallel to the axis of rotation and passing through the point of the rod (1) closest to the axis of rotation, a point which is located at a distance from the axis of rotation of 290 mm, comprised between the distance of 280 mm separating from the axis of rotation the straight line D passing through the point of the coating layer (10) of the anchor rod (1 ) closest to the axis of rotation and the distance of 305 mm separating from the axis of rotation the straight line D 'passing through the point of the coating layer (10) furthest from said axis of rotation.
  • the radially upper end it is located radially, in the case described, at a distance r e from the axis of rotation equal to 335 mm, an amount which is between an amount of 357.5 mm, equal to half sum of 345 mm of the respective distances to the axis of rotation of the straight lines D and D "(410 + 280/2), the straight line D" of greatest axial width passing through the point A being 410 mm from the axis of rotation) increased by the radial half-distance of 12.5 mm between the lines D and D '(305-280/2), and an amount of 332.5 mm, equal to the half-sum 345 mm of the respective distances at the axis of rotation of the straight lines D and D "d of the radial half-distance of 12.5 mm between the straight lines D and D '.
  • the bead B is completed by a single padding (71) and radially above the rod ( 1) and by a protective layer (8).
  • the bead B shown in Figure 3 differs from that shown in Figure 2, firstly by the fact that the rod (1) for anchoring the carcass reinforcement (2) is a rod of the "braided type "(it could be of the" packet "type), which allows a gain in weight, a reduced bulk while maintaining an effective bead cross section which is substantially constant, and a lowering of the cost price of the tire, and on the other hand by the fact that the additional reinforcement reinforcement (6) of bead comprises two plies (61) and (62) of cut reinforcement elements.
  • the first additional reinforcing ply (61) is, as above, axially inside the convex profile of the unreverted part of the carcass reinforcement (2), while the second ply (62) is axially at the center. outside said profile.
  • the radial continuity of the rigidities of this portion of tire is ensured by the mismatching of the respective ends two plies (61) and (62), the ends of the first ply (61) remaining within the limits defined above; however, the radially upper end of the second ply (62) is radially located below the radially upper end of the first ply (61), while the radially lower end of the second ply (62) is very slightly above the right D '.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Tires In General (AREA)
  • Ropes Or Cables (AREA)

Abstract

The invention concerns a tyre comprising at least a radial body ply (2) anchored in each tyre bead (B) to at least one bead wire (1) to form a ply turn-up (20), characterised in that, viewed in meridian cross-section, the body ply (2) has a meridian profile whereof the outline, between point A of the largest axial width and point T tangent with the circumscribed circle at the casing layer (10) of the anchoring bead wire (1), is convex over its whole length, and such that the thickness ε of the tyre bead (B), measured in a plane perpendicular to said meridian profile at a point C of height hc, ranging between 30 and 40 mm and measured relative to the base YY' ranges between 2.5 and 3.0 times the thickness e of the sidewall measured on the straight line D' of the largest axial width, said body ply (2) being reinforced in its non upturned part, with a supplementary reinforcing ply (6) formed by at least one ply (61) of circumferential reinforcing elements axially arranged inside said non-upturned part.

Description

BOURRELET DE PNEUMATIQUE AVEC ELEMENTS DE RENFORT CIRCONFERENTIELS TIRE SADDLE WITH CIRCUMFERENTIAL REINFORCEMENT ELEMENTS
La présente invention concerne un pneumatique à armature de carcasse radiale destiné à porter de lourdes charges, et plus particulièrement un pneumatique de type "Poids Lourds", destiné à équiper des véhicules tels que, par exemple, les camions, tracteurs routiers, autobus, remorques et autres, et plus particulièrement la nouvelle structure de renforcement des bourrelets dudit pneumatique-The present invention relates to a tire with a radial carcass reinforcement intended to carry heavy loads, and more particularly to a tire of the "Heavy Duty" type, intended to equip vehicles such as, for example, trucks, road tractors, buses, trailers and others, and more particularly the new reinforcement structure of the beads of said tire-
En général, un pneumatique du type considéré comprend une armature de carcasse formée d'au moins une nappe de câbles métalliques, ancrée dans chaque bourrelet à au moins une tringle, en formant un retournement. L'armature de carcasse est radialement surmontée d'une armature de sommet, composée d'au moins deux nappes de câbles métalliques, croisés d'une nappe à la suivante en formant avec la direction circonférentielle des angles compris entre 10° et 45°. Les retournements d'armature de carcasse sont généralement renforcés par au moins une nappe de renforcement de bourrelet formée de câbles métalliques orientés à un faible angle par rapport à la direction circonférentielle, compris généralement entre 10° et 30°.In general, a tire of the type under consideration comprises a carcass reinforcement formed of at least one ply of metal cables, anchored in each bead to at least one bead, by forming a reversal. The carcass reinforcement is radially surmounted by a crown reinforcement, composed of at least two plies of metal cables, crossed from one ply to the next, forming angles of between 10 ° and 45 ° with the circumferential direction. Carcass reinforcement upturns are generally reinforced by at least one bead reinforcement ply formed of metal cables oriented at a small angle relative to the circumferential direction, generally between 10 ° and 30 °.
Dans le cas de la présence d'une seule nappe de renforcement de bourrelet, cette dernière est généralement située axialement à l'extérieur, le long du retournement d'armature de carcasse, avec une extrémité radialement supérieure située au dessus ou au dessous de l'extrémité radialement supérieure du retournement d'armature de carcasse. Quant à l'extrémité radialement inférieure d'une telle nappe de renforcement, elle est généralement située sur une droite parallèle à l'axe de rotation et passant approximativement par le centre de gravité de la section méridienne de la tringle d'ancrage de rarmature de carcasse.In the case of the presence of a single bead reinforcement ply, the latter is generally located axially on the outside, along the carcass reinforcement upturn, with a radially upper end situated above or below the radially upper end of the carcass reinforcement upturn. As for the radially lower end of such a reinforcement ply, it is generally located on a straight line parallel to the axis of rotation and passing approximately through the center of gravity of the meridian section of the carcass reinforcement anchor rod.
La solution connue a pour but d'éviter la déradialisation des câbles du retournement de rarmature de carcasse, ainsi que de minimiser les déformations radiales et circonférentielles subies par rextrémité dudit retournement, et par la couche de caoutchouc extérieure recouvrant le bourrelet et assurant la liaison avec la jante.The known solution aims to avoid deradialization of the cables of the carcass reinforcement upturn, as well as to minimize the radial and circumferential deformations undergone by the end of said upturn, and by the outer rubber layer covering the bead and ensuring the connection with the rim.
La durée de vie des pneumatiques "Poids-Lourds", du fait des progrès accomplis, du fait que certains roulages sont rendus moins pénalisants en ce qui concerne l'usure de la bande de roulement, est devenue telle qu'il est encore nécessaire d'améliorer l'endurance des bourrelets. Ladite amélioration doit porter sur la dégradation des couches de caoutchouc au niveau des extrémités de retournement d'armature de carcasse et extrémités radialement extérieures des nappes de renforcement de bourrelets. Plus particulièrement dans le cas de pneumatiques soumis à des roulages prolongés, roulages induisant souvent une température élevée des bourrelets, du fait des températures atteintes par les jantes de montage, les mélanges de caoutchouc en contact avec la jante sont alors sujets à une diminution de leurs rigidités, ainsi qu'à une oxydation plus ou moins lente, d'où une tendance très marquée de l'armature de carcasse à se dérouler autour de la tringle sous l'effet de la pression de gonflage intérieure, malgré la présence d'une ou plusieurs nappes de renforcement de bourrelets. Prennent alors naissance des mouvements de tringle, des déformations de cisaillement à toutes les extrémités de nappes, pour aboutir à la destruction du bourrelet. Ladite amélioration doit aussi, et principalement, porter sur cette deuxième possibilité de dégradation.The lifespan of "Heavy Duty" tires, due to the progress made, the fact that certain runs are made less penalizing as regards the wear of the tread, has become such that it is still necessary to '' improve the endurance of the beads. Said improvement must relate to the degradation of the rubber layers at the ends of the carcass reinforcement upturn and radially outer ends of the bead reinforcement plies. More particularly in the case of tires subjected to prolonged running, rolling often inducing a high temperature of the beads, due to the temperatures reached by the mounting rims, the rubber mixtures in contact with the rim are then subject to a reduction in their rigidities, as well as more or less slow oxidation, hence a very marked tendency for the carcass reinforcement to unwind around the bead wire under the effect of the internal inflation pressure, despite the presence of a or several reinforcing plies of beads. Rod movements then take place, shear deformations at all ends of the sheets, to lead to destruction of the bead. Said improvement must also, and mainly, relate to this second possibility of degradation.
L'armature de carcasse d'un pneumatique radial, monté sur sa jante de service et gonflé à la pression recommandée, a dans un flanc un profil méridien régulièrement convexe entre approximativement les zones de raccordement avec le profil méridien de rarmature de sommet et avec le bourrelet. En particulier, à partir du rayon où rarmature de carcasse subit l'influence de la(des) nappe(s) de renforcement de bourrelets, ladite armature possède un profil méridien sensiblement rectiligne ou même incurvé dans le sens opposé à l'incurvation dans les flancs, c'est-à-dire sensiblement parallèle à la courbure des rebords de jante à partir d'un point d'inflexion situé radialement approximativement au niveau de l'extrémité radialement supérieure de la nappe de renforcement de bourrelets, placée le long du retournement d'armature de carcasse. Une telle architecture conduit à des bourrelets de pneumatiques relativement épais.The carcass reinforcement of a radial tire, mounted on its service rim and inflated to the recommended pressure, has in a sidewall a regularly convex meridian profile between approximately the zones of connection with the meridian profile of reinforcement of apex and with the bead. In particular, from the radius where the carcass reinforcement is influenced by the bead reinforcement ply (s), said reinforcement has a substantially rectilinear meridian profile or even curved in the opposite direction to the curvature in the sidewalls, that is to say substantially parallel to the curvature of the rim flanges from an inflection point located radially approximately at the radially upper end of the bead reinforcement ply, placed along the carcass reinforcement reversal. Such an architecture leads to relatively thick beads of tires.
Les problèmes d'endurance cités ci-dessus, qui sont influencés par la température de fonctionnement des bourrelets, ont été, en très faible partie, résolus par une structure de bourrelet dite amincie, par exemple obtenue par les moyens décrits dans le brevet FR 2 451 016 qui enseigne, dans ce but, de conférer à la paroi extérieure du pneumatique, comprise entre le point où ladite paroi quitte le contact de la jante et le point où ladite paroi atteint sa distance maximale par rapport au plan équatorial, une concavité relativement importante, lorsque le pneumatique est monté sur sa jante de service et gonflé à la pression recommandée. Une telle disposition devient insuffisante, en particulier lorsque le rapport de la hauteur sur jante H sur la largeur axiale maximale S du pneumatique diπiinue, et se doit d'être améliorée lorsque les charges supportées deviennent supérieures ou les pressions de gonflage inférieures aux charges et pressions recommandées.The endurance problems mentioned above, which are influenced by the operating temperature of the beads, have been, in very small part, resolved by a bead structure called thinned, for example obtained by the means described in the patent FR 2 451 016 which teaches, for this purpose, to impart to the outer wall of the tire, comprised between the point where said wall leaves contact with the rim and the point where said wall reaches its maximum distance from the equatorial plane, a relatively concavity important, when the tire is mounted on its service rim and inflated to the recommended pressure. Such an arrangement becomes insufficient, in particular when the ratio of the height on the rim H to the maximum axial width S of the diπiinue tire, and must be improved when the supported loads become higher or the inflation pressures lower than the loads and pressures. recommended.
Les recherches de la demanderesse ont permis d'arriver à la conclusion que ramincissement des bourrelets devait être réalisé non pas par l'extérieur du pneumatique, mais par l'intérieur, et qu'il devait l'être en combinaison avec des caractéristiques précises de renforcement desdits bourrelets.The Applicant's research has led to the conclusion that the beads should be tapered not from the outside of the tire, but from the inside, and that it should be done in combination with precise characteristics of the tire. reinforcement of said beads.
Afin d'améliorer l'endurance des bourrelets d'un pneumatique, pour véhicule destiné à porter de lourdes charges, ledit pneumatique, conforme à l'invention, comprend au moins une armature de carcasse radiale, formée d'au moins une nappe d'éléments de renforcement inextensibles et ancrée dans chaque bourrelet B à au moins une tringle pour former un retournement, chaque bourrelet B étant renforcé par une armature additionnelle de renforcement formée d'éléments métalliques. Il est caractérisé en ce que, vue en section méridienne, l'armature de carcasse a un profil méridien dont le tracé, compris entre le point A de plus grande largeur axiale et le premier point de tangence T avec la couche d'enrobage quasi- circulaire de la tringle d'ancrage, est convexe sur toute sa longueur, et tel que l'épaisseur ε du bourrelet B, mesurée sur une perpendiculaire audit profil méridien en un point C de hauteur hc, comprise entre 30 et 40 mm et mesurée par rapport à la base de bourrelet Y Y', soit comprise entre 2,5 et 3,0 fois répaisseur e du flanc mesurée sur la droite D" ligne de plus grande largeur axiale, ladite armature de carcasse étant renforcée, dans sa partie non retournée, par rarmature additionnelle de renforcement formée d'au moins une nappe d'éléments de renforcement circonférentiels disposée axialement à l'intérieur de ladite partie non retournée.In order to improve the endurance of the beads of a tire, for a vehicle intended to carry heavy loads, said tire, according to the invention, comprises at least one radial carcass reinforcement, formed of at least one ply of inextensible reinforcing elements and anchored in each bead B to at least one rod to form a reversal, each bead B being reinforced by an additional reinforcement frame formed of metallic elements. It is characterized in that, seen in meridian section, the carcass reinforcement has a meridian profile, the layout of which, between point A of greatest axial width and the first point of tangency T with the coating layer almost circular of the anchor rod, is convex over its entire length, and such that the thickness ε of the bead B, measured on a perpendicular to said meridian profile at a point C of height hc, between 30 and 40 mm and measured by relative to the bead base Y Y ', ie between 2.5 and 3.0 times the thickness e of the flank measured on the right D "line of greatest axial width, said carcass reinforcement being reinforced, in its non-turned part , through additional reinforcing reinforcement formed of at least one ply of circumferential reinforcing elements disposed axially inside said non-turned part.
Le point A de plus grande largeur axiale est, par définition, le point du profil méridien d'armature de carcasse correspondant au point de plus grande largeur axiale d'armature de carcasse lorsque le pneumatique est monté sur sa jante de service et gonflé à la pression recommandée et non chargé, et la droite D" de plus grande largeur axiale est la droite parallèle à l'axe de rotation et passant par A.The point A of greater axial width is, by definition, the point of the meridian profile of carcass reinforcement corresponding to the point of greater axial width of carcass reinforcement when the tire is mounted on its service rim and inflated to the recommended pressure and not loaded, and the straight line D "of greatest axial width is the straight line parallel to the axis of rotation and passing through A.
Les éléments de rarmature additionnelle de renforcement sont dits circonférentiels si l'angle qu'ils forment avec la direction circonférentielle est compris entre + 5° et - 5°.The additional reinforcing reinforcement elements are said to be circumferential if the angle they form with the circumferential direction is between + 5 ° and - 5 °.
Le tracé convexe du profil méridien de l'armature de carcasse est généralement formé de plusieurs arcs de cercle adjacents, dont les rayons de courbure sont croissants en allant du point A de plus grande largeur axiale au point de tangence T avec la couche d'enrobage quasi-circulaire de la tringle d'ancrage, mais le tracé entre le point A et le point T peut être convexe et circulaire avec un centre de courbure situé sur la droite de plus grande largeur axiale.The convex line of the meridian profile of the carcass reinforcement is generally formed by several adjacent arcs of circle, the radii of curvature of which increase from the point A of greatest axial width to the point of tangency T with the coating layer. quasi-circular of the anchor rod, but the line between point A and point T can be convex and circular with a center of curvature located on the line of greatest axial width.
La ou les nappes de l'armature additionnelle de renforcement, axialement à l'intérieur de la partie non retournée d'armature de carcasse, auront avantageusement leurs extrémités radialement inférieures radialement au dessous de la droite D', parallèle à l'axe de rotation et passant par le point de la couche d'enrobage de la tringle d'ancrage radialement le plus éloigné de l'axe de rotation, mais au dessus de la droite D, parallèle à l'axe de rotation et passant par le point de la couche d'enrobage de la tringle d'ancrage radialement le plus proche de l'axe de rotation, et des extrémités radialement supérieures situées à une distance radiale de la droite D, comprise entre une quantité égale à la demi-distance radiale entre les droites D et D" augmentée de la demi-distance radiale entre les droites D et D', et une quantité égale à la demi-distance radiale entre les droites D et D" diminuée de la demi- distance radiale entre les droites D et D'.The ply (s) of the additional reinforcement armature, axially inside the non-turned part of the carcass reinforcement, will advantageously have their ends radially lower radially below the straight line D ', parallel to the axis of rotation and passing through the point of the coating layer of the anchor rod radially furthest from the axis of rotation, but above the straight line D, parallel to the axis of rotation and passing through the point of the coating layer of the anchor rod radially closest to the axis of rotation, and radially upper ends situated at a radial distance from the straight line D, between an amount equal to the radial half-distance between the straight lines D and D "increased by the radial half-distance between the lines D and D ', and an amount equal to the radial half-distance between the lines D and D "minus the radial half-distance between the lines D and D'.
Cette structure permet ainsi une reprise partielle des efforts de tension méridiens subis par rarmature de carcasse, et ainsi mήiimise les déformations radiales en extrémités de retournement d'armature de carcasse, quelles que soient les conditions de roulage.This structure thus allows a partial recovery of the meridian tension forces undergone by carcass reinforcement, and thus minimizes the radial deformations at the ends of the carcass reinforcement upturn, whatever the driving conditions.
La reprise des efforts sera d'autant plus importante que les éléments de renforcement de rarmature additionnelle seront plus nombreux ; ils seront préférentiellement métalliques, en acier, parallèles entre eux dans la nappe additionnelle et jointifs sur toute la largeur de rarmature de renforcement. Des éléments de renforcement sont dits jointifs, si, dans la direction perpendiculaire aux dits éléments, la distance séparant deux éléments adjacents est réduite au maximum.The resumption of efforts will be all the more important as the reinforcing elements of additional reinforcement will be more numerous; they will preferably be metallic, steel, mutually parallel in the additional ply and joined over the entire width of the reinforcing reinforcement. Reinforcement elements are said to be contiguous if, in the direction perpendicular to said elements, the distance separating two adjacent elements is reduced to the maximum.
La reprise des efforts de tension méridienne d'une armature de carcasse est connue en soi par de nombreux documents. Le brevet FR 750 726 de la demanderesse enseigne le collage des nappes d'armature de carcasse à des armatures auxiliaires, chacune formée de fil enroulé en spirale et présentant en conséquence une flexibilité notable dans le sens transversal. Ledit collage est réalisé de sorte que deux nappes d'armature de carcasse enserrent une armature auxiliaire, ledit enserrement se faisant en l'absence de tringle et de retournement d'armature de carcasse.The resumption of the meridian tension forces of a carcass reinforcement is known in itself from numerous documents. Patent FR 750 726 of the applicant teaches the bonding of carcass reinforcement plies to auxiliary reinforcements, each formed from wire wound in a spiral and having consequently a notable flexibility in the transverse direction. Said bonding is carried out so that two carcass reinforcement plies enclose an auxiliary reinforcement, said clamping being effected in the absence of rod and carcass reinforcement flipping.
Le brevet FR 1 169 474 enseigne aussi de supprimer la tringle usuellement employée par des petites nappes de fils ou câbles métalliques inclinées sur le parallèle d'accrochage, l'angle d'inclinaison pouvant descendre jusqu'à 5°, la (les) nappe(s) d'armature de carcasse étant retournées on non.Patent FR 1,169,474 also teaches to remove the rod usually used by small plies of metal wires or cables inclined on the attachment parallel, the angle of inclination being able to descend to 5 °, the ply (s) (s) of carcass reinforcement being returned or not.
Le brevet FR 1 234 995 prévoit le remplacement des éléments de renforcement usuellement obliques de la(des) nappe(s) de renforcement de bourrelet destinée(s) à réduire les mouvements de l'accrochage contre le rebord de jante, par des éléments circonférentiels, rarmature de renforcement pouvant être disposée entre la partie principale de l'armature de carcasse et le retournement de ladite armature, ou axialement à l'extérieur dudit retournement d'armature de carcasse.Patent FR 1 234 995 provides for the replacement of the usually oblique reinforcement elements of the bead reinforcement ply (s) intended to reduce the movements of the attachment against the rim flange, by circumferential elements. , reinforcing reinforcement which can be arranged between the main part of the carcass reinforcement and the reversal of said reinforcement, or axially outside said carcass reinforcement reversal.
Nous retrouvons les mêmes armatures de renforcement de bourrelet à éléments circonférentiels dans le brevet FR 1 256 432, les dits éléments étant destinés à la reprise dans son intégralité des efforts de tension d'armature de carcasse, et dans le cas de pneumatiques pour véhicules de tourisme, en l'absence de tringles d'ancrage ou toute autre nappe de renforcement.We find the same bead reinforcement reinforcements with circumferential elements in patent FR 1 256 432, the said elements being intended for the recovery in its entirety of the stresses of carcass reinforcement tension, and in the case of tires for vehicles of tourism, in the absence of anchor rods or any other reinforcement ply.
Le document FR 2 055 988 décrit un certain nombre d'applications possibles d'une armature de renforcement de bourrelet à éléments circonférentiels, en particulier l'utilisation d'une telle armature au lieu et place de l'armature usuelle à éléments obliques disposés axialement à l'extérieur du retournement d'armature de carcasse.Document FR 2 055 988 describes a certain number of possible applications of a reinforcement of a bead with elements circumferential, in particular the use of such a reinforcement instead of the usual reinforcement with oblique elements arranged axially outside the carcass reinforcement upturn.
Non seulement la combinaison du profil méridien conforme à l'invention avec la présence d'une armature de renforcement de bourrelet, à éléments circonférentiels, et dont au moins une nappe est disposée à l'intérieur de la partie non retournée ou principale de l'armature de carcasse, permet l'amélioration de l'endurance des bourrelets, mais elle permet en outre d'obtenir une très nette diminution du poids d'un pneumatique tout en n'altérant pas ses propriétés, lorsque l'on combine la présence d'une armature de renforcement de bourrelet, décrite ci-dessus, au remplacement de la tringle à fils métalliques rectangulaires, généralement utilisée dans le type de pneumatique considéré, par une tringle plus économique de type tressé, c'est-à-dire formée d'un tressage hélicoïdal de plusieurs fils métalliques, ou une tringle de type paquet à section polygonale, c'est-à-dire une tringle obtenue par l'enroulement sur une forme d'un fil métallique conduisant à plusieurs couches de différentes largeurs. Les types de tringle ci-dessus permettent un moindre encombrement du fait de la forme de leur section transversale, mais aussi du fait que la reprise des efforts par rarmature additionnelle permet une diminution sensible des dites sections . Quelle que soit le type de tringle, tressé ou paquet, la section transversale peut être diminuée de 30 à 50%, ce qui conduit par rapport à l'application de l'invention au cas d'une tringle à fils rectangulaires plus encombrante, à avoir soit une épaisseur de bourrelet plus amincie, soit une épaisseur de bourrelet constante mais avec un profil méridien dit plus tendu, dans le sens où sa convexité est moins prononcée. L'armature de renforcement de bourrelet ainsi décrite peut être réalisée séparément par enroulement en spirale sur un support horizontal de forme appropriée, et ensuite transférée sur l'ébauche de pneumatique non vulcanisée. La fabrication d'un tel pneumatique sera cependant avantageusement facilitée par l'emploi, à titre d'éléments de renforcement, de tronçons ou d'ensembles ou groupes de tronçons de câbles, de longueur circonférentielle comprise entre 0,2 et 0,4 fois la longueur circonférentielle moyenne de l'armature de renforcement, ce qui permet la pose de l'armature de renforcement de bourrelet sur le tambour de confection de l'ébauche crue d'armature de carcasse et la mise sous forme torique de la dite ébauche sans difficultés majeures, et ladite longueur moyenne étant mesurée à la pose sur ledit tambour de confection. Les interstices ou coupures circonférentielles entre éléments coupés seront préférentiellement décalés les uns par rapport aux autres.Not only the combination of the meridian profile in accordance with the invention with the presence of a bead reinforcement reinforcement, with circumferential elements, and of which at least one ply is disposed inside the unreturned or main part of the carcass reinforcement, improves the endurance of the beads, but it also makes it possible to obtain a very marked reduction in the weight of a tire while not altering its properties, when the presence of a bead reinforcement reinforcement, described above, to replace the rod of rectangular metal wires, generally used in the type of tire considered, by a more economical bead of the braided type, that is to say formed of '' a helical braiding of several metal wires, or a packet rod of polygonal section, that is to say a rod obtained by winding on a form of a metal wire leading to more several layers of different widths. The above rod types allow less space due to the shape of their cross section, but also because the resumption of forces by additional reinforcement allows a significant reduction of said sections. Whatever the type of rod, braided or bundle, the cross section can be reduced by 30 to 50%, which leads, compared to the application of the invention, in the case of a rod with more bulky rectangular wires, to have either a more thinned bead thickness, or a constant bead thickness but with a so-called tauter meridian profile, in the sense that its convexity is less pronounced. The bead reinforcement thus described can be produced separately by spiral winding on a horizontal support of suitable shape, and then transferred to the unvulcanized tire blank. The manufacture of such a tire will however advantageously be facilitated by the use, as reinforcing elements, of sections or of sets or groups of sections of cables, of circumferential length between 0.2 and 0.4 times the average circumferential length of the reinforcing reinforcement, which allows the fitting of the bead reinforcing reinforcement on the drum for making the raw carcass reinforcement blank and the toroidal shaping of said blank without major difficulties, and said average length being measured when laid on said making drum. The circumferential gaps or cuts between cut elements will preferably be offset with respect to each other.
Il peut être aussi avantageux, afin de conférer au bourrelet de pneumatique une rigidité transversale supérieure, tout en permettant une amélioration accrue de l'endurance des bourrelets, que soit présente dans l'armature de renforcement additionnelle au moins une nappe formée d'éléments métalliques circonférentiels et disposée axialement à l'extérieur de la partie non retournée de l'armature de carcasse. La dite nappe additionnelle, axialement à l'extérieur, aura son extrémité radialement supérieure située radialement de la même manière que la ou les nappes axialement à l'intérieur, alors que l'extrémité radialement mférieure de cette deuxième nappe sera avantageusement située entre la droite D' et une droite parallèle à D' radialement à l'extérieur et distante radialement de D' d'une quantité égale à la distance radiale séparant D' de D. Les éléments de renforcement de ladite deuxième nappe seront préférentiellement des tronçons ou ensemble de tronçons de câbles métalliques en acier de longueur circonférentielle au plus égale à 0,4 fois la longueur circonférentielle moyenne de rarmature de renforcement ainsi formée.It can also be advantageous, in order to give the tire bead a greater transverse rigidity, while allowing an increased improvement in the endurance of the beads, that at least one ply formed of metallic elements is present in the additional reinforcement frame. circumferential and disposed axially outside the unreturned part of the carcass reinforcement. Said additional ply, axially on the outside, will have its radially upper end situated radially in the same way as the ply (s) axially on the inside, while the radially lower end of this second ply will advantageously be located between the right From and a parallel line à D 'radially outside and radially distant from D' by an amount equal to the radial distance separating D 'from D. The reinforcing elements of said second ply will preferably be sections or set of sections of steel wire cables of circumferential length at most equal to 0.4 times the average circumferential length of the reinforcing reinforcement thus formed.
Les caractéristiques de l'invention seront mieux comprises à l'aide de la description qui suit et qui se réfère au dessin, illustrant à titre non limitatif des exemples d'exécution, et sur lequel :The characteristics of the invention will be better understood with the aid of the description which follows and which refers to the drawing, illustrating non-limiting examples of execution, and in which:
- la figure 1 représente schématiquement, vue en section transversale, une structure de pneumatique, connue par l'état de la technique,FIG. 1 schematically represents, seen in cross section, a tire structure, known from the state of the art,
- la figure 2 représente schématiquement et en vue agrandie une première variante de bourrelet conforme à l'invention, dans sa version la plus dépouillée,FIG. 2 schematically represents an enlarged view of a first variant of bead according to the invention, in its most stripped down version,
- la figure 3 représente schématiquement une deuxième variante de bourrelet conforme à l'invention, la tringle étant une tringle tressée, et avec une armature de renforcement de bourrelet à deux nappes.- Figure 3 shows schematically a second variant of bead according to the invention, the rod being a braided rod, and with a reinforcement of bead reinforcement with two plies.
Le pneumatique P représenté sur la figure 1 est un pneumatique de dimension 315/80 R 22,5, destiné à être monté sur une jante comportant des sièges de jante inclinés à 15°. Ledit pneumatique comprend une bande de roulement (4) réunie à deux bourrelets B par l'intermédiaire de deux flancs (5). Chaque bourrelet B est renforcé par une tringle (1) formée par l'enroulement sur une forme appropriée d'un fil à section quadrilatère jusqu'à obtention de plusieurs rangées de fils radialement juxtaposées. Autour de ladite tringle (1) est ancrée une armature de carcasse (2), composée d'une seule nappe de câbles métalliques. L'ancrage se fait par un retournement (20) autour de la couche (10) de mélange caoutchouteux qui recouvre la tringle (1), la distance radiale h, séparant l'extrémité radialement supérieure dudit retournement (20) de la droite YY' parallèle à l'axe de rotation et définissant le diamètre nominal du bourrelet (qui est le même, dans le cas décrit, que le diamètre de la jante de service), étant égale, dans l'exemple étudié du pneumatique de dimension 315/80 R 22.5, à 37 mm. Entre l'armature de carcasse (2) et son retournement (20), radialement au dessus de la tringle (1), est disposé un bourrage tringle (71) en mélange caoutchouteux de dureté Shore généralement élevée. Axialement à l'extérieur du retournement (20), se trouve une nappe de renforcement (6) formée de câbles métalliques inextensibles faiblement orientés par rapport à la direction circonférentielle, et dont l'extrémité radialement supérieure est plus éloignée de l'axe de rotation que l'extrémité supérieure du retournement (20) d'armature de carcasse (2). Ladite nappe (6) est séparée du bourrage tringle (71) par un deuxième bourrage (72) de remplissage, et du mélange caoutchouteux de protection (8), qui entoure le bourrelet B, par un profilé de mélange caoutchouteux (73).The tire P shown in FIG. 1 is a tire of dimension 315/80 R 22.5, intended to be mounted on a rim comprising rim seats inclined at 15 °. Said tire comprises a tread (4) joined to two beads B by means of two sidewalls (5). Each bead B is reinforced by a rod (1) formed by winding on a suitable form a wire with a quadrilateral section until several rows of radially juxtaposed wires are obtained. Around said rod (1) is anchored a carcass reinforcement (2), composed of a single ply of metal cables. The anchoring is done by a reversal (20) around the layer (10) of rubber mixture which covers the rod (1), the radial distance h, separating the radially upper end of said reversal (20) from the straight line YY ' parallel to the axis of rotation and defining the nominal diameter of the bead (which is the same, in the case described, as the diameter of the service rim), being equal, in the example studied of the tire of dimension 315/80 R 22.5, at 37 mm. Between the carcass reinforcement (2) and its upturn (20), radially above the rod (1), is disposed a rod stuffing (71) in a rubber mixture of generally high Shore hardness. Axially outside the turnaround (20), there is a reinforcement ply (6) formed of inextensible metallic cables weakly oriented relative to the circumferential direction, and the radially upper end of which is further from the axis of rotation. that the upper end of the carcass reinforcement upturn (20) (2). Said ply (6) is separated from the rod stuffing (71) by a second filling stuffing (72), and from the protective rubber mixture (8), which surrounds the bead B, by a rubber mixture profile (73).
Le bourrelet B du pneumatique de même dimension, conforme à l'invention et montré sur la figure 2, est, de manière identique, renforcé par une tringle (1) à fils rectangulaires, et entouré d'une couche (10) de mélange caoutchouteux à haut module d'élongation, autour de laquelle vient s'ancrer rarmature de carcasse (2) pour former un retournement (20). Ledit bourrelet B présente en combinaison les deux caractéristiques essentielles suivantes : l'armature de carcasse (2) possède, vue en section méridienne, un profil méridien, entre le point A de plus grande largeur axiale et le premier point de tangence T dudit profil avec la couche d'enrobage (10) quasi-circulaire de la tringle (1), qui est de manière continue convexe, et l'armature de renforcement de bourrelet (6), composée, dans l'exemple décrit, d'une seule nappe (6) d'éléments circonférentiels, est placée axialement à l'intérieur de la partie non retournée de l'armature de carcasse (2) et non axialement à l'extérieur du retournement (20) de rarmature de carcasse (2). La convexité du profil méridien, continue du point A au point T, permet, par rapport au pneumatique de l'art antérieur avec un tracé de profil passant de convexe à concave, permet un amincissement non négligeable du bourrelet B. Si nous considérons l'épaisseur ε du bourrelet comme étant la distance, mesurée sur une perpendiculaire au profil méridien d'armature de carcasse abaissée du point C dudit profil méridien de hauteur h , comprise entre 30 et 40 mm et mesurée par rapport à la droite YY', le bourrelet, conforme à l'invention, a une épaisseur égale à 2,9 fois l'épaisseur e du flanc, mesurée sur la droite D" parallèle à l'axe de rotation et de plus grande largeur axiale, alors que le bourrelet B du pneumatique de la figure 1 a une épaisseur, mesurée dans les mêmes conditions, égale à 3,4 fois l'épaisseur e. Ledit amincissement, visualisé sur la figure 2 par la différence des tracés des parois intérieures respectivement d'un pneumatique de l'art antérieur et d'un pneumatique conforme à l'invention, ne peut donner de résultats satisfaisants que si le bourrelet B est renforcé par au moins une nappe additionnelle de renforcement (61) d'éléments à haut module d'élasticité et disposés circonférentiellement, ladite nappe (61) étant située axialement à l'intérieur de l'armature de carcasse (2) dont le profil méridien est convexe. Les éléments de renforcement de la nappe (61) sont des tronçons de câbles 27 x 23. métalliques, la longueur desdits éléments ou tronçons de câbles étant égale au quart de la longueur circonférentielle de ladite nappe (61) mesurée lors de sa pose sur le tambour de confection de l'ébauche d'armature de carcasse. Les espaces entre extrémités d'éléments sont de faible amplitude : 3 mm (mesurés aussi lors de la pose) et sont décalés circonférentiellement entre eux.The bead B of the tire of the same dimension, in accordance with the invention and shown in FIG. 2, is, in an identical manner, reinforced by a bead wire (1) with rectangular wires, and surrounded by a layer (10) of rubber mixture. with a high elongation module, around which is anchored carcass reinforcement (2) to form an upturn (20). Said bead B has the following two essential characteristics in combination: the carcass reinforcement (2) has, seen in meridian section, a meridian profile, between point A of greater axial width and the first point of tangency T of said profile with the quasi-circular coating layer (10) of the rod (1), which is continuously convex, and the bead reinforcement reinforcement (6), composed, in the example described, of a single ply (6) of circumferential elements, is placed axially inside the non-turned part of the carcass reinforcement (2) and not axially outside the reversal (20) of the carcass reinforcement (2). The convexity of the meridian profile, continuous from point A to point T, allows, compared to the tire of the prior art with a profile tracing passing from convex to concave, allows a non-negligible thinning of the bead B. If we consider the thickness ε of the bead as the distance, measured on a perpendicular to the meridian profile of the carcass reinforcement lowered from point C of said meridian profile of height h, between 30 and 40 mm and measured relative to the straight line YY ', the bead , in accordance with the invention, has a thickness equal to 2.9 times the thickness e of the sidewall, measured on the straight line D "parallel to the axis of rotation and of greater axial width, while the bead B of the tire of FIG. 1 has a thickness, measured under the same conditions, equal to 3.4 times the thickness e. Said thinning, visualized in FIG. 2 by the difference of the plots of the interior walls respectively of a tire of the art ant laughing and a tire according to the invention, can not give satisfactory results if the bead B is reinforced by at least one additional reinforcement ply (61) of upper elements modulus of elasticity and arranged circumferentially, said ply (61) being located axially inside the carcass reinforcement (2) whose meridian profile is convex. The reinforcing elements of the ply (61) are sections of 27 x 23 metallic cables, the length of said elements or sections of cables being equal to a quarter of the circumferential length of said ply (61) measured when it is laid on the drum for making the carcass reinforcement blank. The spaces between the ends of the elements are of small amplitude: 3 mm (also measured during installation) and are offset circumferentially between them.
L'extrémité radialement inférieure de la nappe (61) est sensiblement disposée sur une droite parallèle à l'axe de rotation et passant par le point de la tringle (1) le plus proche de l'axe de rotation, point qui est situé à une distance de l'axe de rotation de 290 mm, comprise entre la distance de 280 mm séparant de l'axe de rotation la droite D passant par le point de la couche d'enrobage (10) de la tringle d'ancrage (1) le plus proche de l'axe de rotation et la distance de 305 mm séparant de l'axe de rotation la droite D' passant par le point de la couche d'enrobage (10) le plus éloigné dudit axe de rotation.The radially lower end of the ply (61) is substantially disposed on a straight line parallel to the axis of rotation and passing through the point of the rod (1) closest to the axis of rotation, a point which is located at a distance from the axis of rotation of 290 mm, comprised between the distance of 280 mm separating from the axis of rotation the straight line D passing through the point of the coating layer (10) of the anchor rod (1 ) closest to the axis of rotation and the distance of 305 mm separating from the axis of rotation the straight line D 'passing through the point of the coating layer (10) furthest from said axis of rotation.
Quant à rextrémité radialement supérieure, elle est située radialement, dans le cas décrit, à une distance re de l'axe de rotation égale à 335 mm, quantité qui est comprise entre une quantité de 357,5 mm, égale à la demi-somme de 345 mm des distances respectives à l'axe de rotation des droites D et D" (410 + 280/2), la droite D" de plus grande largeur axiale passant par le point A étant à 410 mm de l'axe de rotation) augmentée de la demi-distance radiale de 12,5 mm entre les droites D et D' (305- 280/2), et une quantité de 332,5 mm, égale à la demi-somme 345 mm des distances respectives à l'axe de rotation des droites D et D" d inuée de la demi-distance radiale de 12,5 mm entre les droites D et D'. Le bourrelet B est complété par un bourrage (71) unique et radialement au-dessus de la tringle (1) et par une couche de protection (8).As for the radially upper end, it is located radially, in the case described, at a distance r e from the axis of rotation equal to 335 mm, an amount which is between an amount of 357.5 mm, equal to half sum of 345 mm of the respective distances to the axis of rotation of the straight lines D and D "(410 + 280/2), the straight line D" of greatest axial width passing through the point A being 410 mm from the axis of rotation) increased by the radial half-distance of 12.5 mm between the lines D and D '(305-280/2), and an amount of 332.5 mm, equal to the half-sum 345 mm of the respective distances at the axis of rotation of the straight lines D and D "d of the radial half-distance of 12.5 mm between the straight lines D and D '. The bead B is completed by a single padding (71) and radially above the rod ( 1) and by a protective layer (8).
Le bourrelet B, montré sur la figure 3 diffère de celui montré sur la figure 2, d'une part par le fait que la tringle (1) d'ancrage de l'armature de carcasse (2) est une tringle de type "tressé" (elle pourrait être du type "paquet"), ce qui permet un gain de poids, un encombrement moindre tout en conservant une section transversale efficace de tringle sensiblement constante, et un abaissement du prix de revient du pneumatique, et d'autre part par le fait que l'armature de renforcement (6) additionnelle de bourrelet comprend deux nappes (61) et (62) d'éléments de renforcement coupés. Si l'on compare le bourrelet de la figure 3 à celui de la figure 2, et en particulier les profils méridiens respectifs d'armature de carcasse, il est nettement visible que l'épaisseur ε du bourrelet, distance toujours mesurée sur la perpendiculaire au profil méridien d'armature de carcasse abaissée du même point C dudit profil méridien , est plus faible et égale dans cet exemple à 2,5 fois l'épaisseur e du flanc de 8,9 mm, mesurée sur la droite D" parallèle à l'axe de rotation et de plus grande largeur axiale.The bead B, shown in Figure 3 differs from that shown in Figure 2, firstly by the fact that the rod (1) for anchoring the carcass reinforcement (2) is a rod of the "braided type "(it could be of the" packet "type), which allows a gain in weight, a reduced bulk while maintaining an effective bead cross section which is substantially constant, and a lowering of the cost price of the tire, and on the other hand by the fact that the additional reinforcement reinforcement (6) of bead comprises two plies (61) and (62) of cut reinforcement elements. If we compare the bead of Figure 3 to that of Figure 2, and in particular the respective meridian profiles of carcass reinforcement, it is clearly visible that the thickness ε of the bead, distance always measured on the perpendicular to the meridian profile of carcass reinforcement lowered by the same point C of said meridian profile, is lower and equal in this example to 2.5 times the thickness e of the flank of 8.9 mm, measured on the right D "parallel to l 'axis of rotation and greater axial width.
La première nappe additionnelle de renforcement (61) est, comme ci-dessus, axialement à l'intérieur du profil convexe de la partie non retournée d'armature de carcasse (2), alors que la seconde nappe (62) est axialement à l'extérieur dudit profil. La continuité radiale des rigidités de cette partie de pneumatique est assurée par la non concordance des extrémités respectives des deux nappes (61) et (62), les extrémités de la première nappe (61) restant dans les limites précédemment définies ; cependant, l'extrémité radialement supérieure de la deuxième nappe (62) est radialement située au dessous de l'extrémité radialement supérieure de la première nappe (61), alors que l'extrémité radialement inférieure de la deuxième nappe (62) est très légèrement au dessus de la droite D'.The first additional reinforcing ply (61) is, as above, axially inside the convex profile of the unreverted part of the carcass reinforcement (2), while the second ply (62) is axially at the center. outside said profile. The radial continuity of the rigidities of this portion of tire is ensured by the mismatching of the respective ends two plies (61) and (62), the ends of the first ply (61) remaining within the limits defined above; however, the radially upper end of the second ply (62) is radially located below the radially upper end of the first ply (61), while the radially lower end of the second ply (62) is very slightly above the right D '.
Des pneumatiques PQ conformes à l'invention et tels que décrits dans le passage de la description correspondant à la figure 2, ont été comparés :PQ tires in accordance with the invention and as described in the passage of the description corresponding to FIG. 2, were compared:
- à des pneumatiques usuels Pχ5 c'est à dire comprenant des bourrelets d'épaisseur usuelle et où la nappe de renforcement de bourrelet est une nappe de câbles métalliques continus orientés à 22° par rapport à la direction circonférentielle et disposée axialement à l'extérieur du retournement d'armature de carcasse, telle que montrée sur la figure 1 du dessin, et- to conventional tires Pχ 5, that is to say comprising beads of usual thickness and where the bead reinforcement ply is a ply of continuous metal cables oriented at 22 ° with respect to the circumferential direction and disposed axially at outside of the carcass reinforcement upturn, as shown in FIG. 1 of the drawing, and
- à des pneumatiques PA, comprenant des bourrelets à épaisseur normale, mais avec une nappe de renforcement de bourrelet positionnée axialement à l'intérieur de l'armature de carcasse et formée des mêmes tronçons de câbles, orientés circonférentiellement, et- PA tires, comprising beads of normal thickness, but with a bead reinforcement ply positioned axially inside the carcass reinforcement and formed of the same sections of cables, oriented circumferentially, and
- à des pneumatiques Pβ comprenant des bourrelets à épaisseur amoindrie avec une nappe de renforcement de bourrelet disposée axialement à l'extérieur du retournement d'armature de carcasse, et formée de câbles métalliques continus orientés d'un angle de 22° par rapport à la direction circonférentielle. La comparaison s'est réalisée sur deux critères de qualité, fondamentaux pour l'endurance des bourrelets de pneumatiques : l'endurance sous une surcharge, et l'endurance sur jante chauffante. Dans les mêmes conditions de roulage pour toutes les enveloppes testées, les pneumatiques usuels PT font en moyenne (2 pneumatiques testés par catégorie) 53 000 km en roulage avec surcharge surchargé et 5 200 km en roulage jante chauffante. Les pneumatiques PA ont réalisé respectivement 101 000 km et 8 100 km, alors que les pneumatiques Pg réalisaient 32 000 km et 3 300 km respectivement, et les pneumatiques Pc, conformes à l'invention, 105 000 km et 8 200 km. Les résultats ci-dessus mettent parfaitement en valeur l'effet bénéfique du remplacement de l'armature de renforcement, d'éléments à angle, sur le retournement d'armature de carcasse par une armature de renforcement d'éléments circonférentiels discontinus axialement à l'intérieur de la partie principale de l'armature de carcasse. Plus encore les dits résultats mettent en valeur l'effet de synergie manifeste existant entre les deux paramètres que sont l'épaisseur du bourrelet et le choix judicieux des structure et position de l'armature de renforcement de bourrelet : par exemple en roulage sur jante chauffante, si l'armature de renforcement à câbles circonférentiels discontinus placée à l'intérieur de rarmature de carcasse permet un gain de moyen de 2 900 km dans le cas d'un bourrelet à épaisseur usuelle, le même changement permet un gain de 4 900 km dans le cas d'un bourrelet aminci. Il en est de même des résultats en roulage sous surcharge : le changement d'armature de renforcement provoque un gain de 48 000 km dans le cas d'un bourrelet à épaisseur usuel, alors que le même changement provoque un gain de 73 000 km, c'est-à-dire presque le double, dans le cas d'un bourrelet aminci. Cet effet de synergie, insoupçonné jusqu'alors, permet de conférer à un pneumatique dont les bourrelets présentent la combinaison de paramètres décrits, une endurance très nettement supérieure à ce qui est connu aujourd'hui, tout en permettant un allégement du poids total du pneumatique et une légère diminution de son prix de revient. - Pβ tires comprising beads of reduced thickness with a bead reinforcement ply disposed axially outside the carcass reinforcement upturn, and formed of continuous metal cables oriented at an angle of 22 ° relative to the circumferential direction. The comparison was carried out on two quality criteria, fundamental for the endurance of tire beads: endurance under an overload, and endurance on a heated rim. Under the same driving conditions for all the casings tested, the usual PT tires make an average (2 tires tested per category) 53,000 km in driving with overloaded overload and 5,200 km in rolling with heated rim. The PA tires covered 101,000 km and 8,100 km respectively, while the Pg tires covered 32,000 km and 3,300 km respectively, and the Pc tires, according to the invention, 105,000 km and 8,200 km. The above results perfectly highlight the beneficial effect of replacing the reinforcing reinforcement, of angled elements, on the inversion of carcass reinforcement by a reinforcement of circumferential elements discontinuous axially at the inside the main part of the carcass reinforcement. Even more, the said results highlight the obvious synergistic effect existing between the two parameters which are the thickness of the bead and the judicious choice of the structure and position of the bead reinforcement frame: for example when rolling on a heated rim. , if the reinforcement reinforcement with discontinuous circumferential cables placed inside the carcass reinforcement allows an average gain of 2,900 km in the case of a bead with usual thickness, the same change allows a gain of 4,900 km in the case of a thinned bead. It is the same for the results in driving under overload: the change of reinforcement reinforcement causes a gain of 48,000 km in the case of a bead with usual thickness, while the same change causes a gain of 73,000 km, that is to say almost double, in the case of a thinned bead. This synergistic effect, previously unsuspected, gives a tire whose beads have the combination of parameters described, an endurance very much greater than what is known today, while allowing a reduction in the total weight of the tire and a slight reduction in its cost price.

Claims

REVENDICATIONS
Pneumatique comprenant au moins une armature de carcasse radiale (2), formée d'au moins une nappe (2) d'éléments de renforcement inextensibles et ancrée dans chaque bourrelet B à une tringle (1) pour former un retournement (20), chaque bourrelet B étant renforcé par une armature de renforcement additionnelle (6) d'au moins une nappe (61) formée d'éléments métalliques, caractérisé en ce que, vue en section méridienne, rarmature de carcasse (2) a un profil méridien dont le tracé, compris entre le point A de plus grande largeur axiale et le point de tangence T avec la couche d'enrobage (10) quasi- circulaire de la tringle d'ancrage (1), est convexe sur toute sa longueur, et tel que l'épaisseur ε du bourrelet B, mesurée sur une perpendiculaire audit profil méridien en un point C de hauteur hc, comprise entre 30 et 40 mm et mesurée par rapport à la base de bourrelet YY', soit comprise entre 2,5 et 3,0 fois l'épaisseur e du flanc mesurée sur la droite D" de plus grande largeur axiale, ladite armature de carcasse (2) étant renforcée dans sa partie non retournée, par rarmature additionnelle de renforcement (6) formée d'au moins une nappe (61) d'éléments de renforcement circonférentiels disposée axialement à l'intérieur de ladite partie non retournée. - Pneumatique selon le revendication 1, caractérisé en ce que la (les) nappe(s) (61) de rarmature additionnelle de renforcement (6), axialement à l'intérieur de la partie non retournée d'armature de carcasse (2), a (ont) avantageusement son (leurs) extrémité(s) radialement inférieure(s) radialement au dessous de la droite D', parallèle à l'axe de rotation et passant par le point de la couche d'enrobage (10) de la tringle d'ancrage (1) radialement le plus éloigné de l'axe de rotation, mais au dessus de la droite D, parallèle à l'axe de rotation et passant par le point de la couche d'enrobage (10) de la tringle d'ancrage (1) radialement le plus proche de l'axe de rotation, et une (des) extrémité(s) radialement supérieure(s) située(s) à une distance radiale de la droite D, comprise entre une quantité égale à la demi-distance radiale entre les droites D et D" augmentée de la demi- distance radiale entre les droites D et D', et une quantité égale à la demi-distance radiale entre les droites D et D" diminuée de la demi- distance radiale entre les droites D et D'.Tire comprising at least one radial carcass reinforcement (2), formed of at least one ply (2) of inextensible reinforcing elements and anchored in each bead B to a bead wire (1) to form a reversal (20), each bead B being reinforced by an additional reinforcement armature (6) of at least one ply (61) formed of metallic elements, characterized in that, seen in meridian section, carcass reinforcement (2) has a meridian profile whose line, between the point A of greatest axial width and the point of tangency T with the almost circular coating layer (10) of the anchor rod (1), is convex over its entire length, and such that the thickness ε of the bead B, measured on a perpendicular to said meridian profile at a point C of height h c , between 30 and 40 mm and measured relative to the bead base YY ', ie between 2.5 and 3 , 0 times the thickness e of the flank measured on the right D "plus gra n axial width, said carcass reinforcement (2) being reinforced in its non-turned part, by additional reinforcement reinforcement (6) formed of at least one ply (61) of circumferential reinforcement elements disposed axially inside said part not returned. - A tire according to claim 1, characterized in that the ply (s) (61) of additional reinforcing reinforcement (6), axially inside the unreverted part of the carcass reinforcement (2), advantageously has its radially lower end (s) radially below the straight line D ', parallel to the axis of rotation and passing through the point of the coating layer (10) of the anchor rod (1) radially furthest from the axis of rotation, but above the straight line D, parallel to the axis of rotation and passing through the point of the coating layer (10) of the rod anchor (1) radially closest to the axis of rotation, and one (s) end (s) radially upper (s) located (s) at a radial distance from the straight line D, between an amount equal to the radial half-distance between the lines D and D "increased by the radial half-distance between the lines D and D ', and an amount equal to the half-distance radial between lines D and D "minus the radial half distance between lines D and D '.
- Pneumatique selon l'une des revendications 1 ou 2, caractérisé en ce que rarmature de -πεMfbrcement additionnelle (6) comprend en outre au moins une nappe (62), formée d'éléments métalliques circonférentiels et disposée axialement à l'extérieur de la partie non retournée de rarmature de carcasse (2), ladite nappe additionnelle (62), ayant son extrémité radialement supérieure située radialement de la même manière que la ou les nappes (61) axialement à l'intérieur, alors que son extrémité radialement inférieure est située entre la droite D' et une droite parallèle à D' radialement à l'extérieur, distante radialement de D' d'une quantité égale à la distance radiale séparant D' de D.- Tire according to one of claims 1 or 2, characterized in that the additional reinforcement -πεMfbrcement (6) further comprises at least one ply (62), formed of circumferential metallic elements and arranged axially outside the unreverted part of the carcass reinforcement (2), said additional ply (62), having its radially upper end situated radially in the same manner as the ply (s) (61) axially inside, while its radially lower end is located between line D 'and a straight parallel to D 'radially outside, radially distant from D' by an amount equal to the radial distance separating D 'from D.
- Pneumatique selon l'une des revendications 1 à 3, caractérisé en ce que les éléments de renforcement circonférentiels de rarmature additionnelle (6) sont métalliques, en acier, et jointifs sur toute la largeur de ladite armature.- A tire according to one of claims 1 to 3, characterized in that the circumferential reinforcing elements of additional reinforcement (6) are metallic, made of steel, and joined over the entire width of said reinforcement.
- Pneumatique selon l'une des revendications 1 à 4, caractérisé en ce que la tringle d'ancrage (1) de rarmature de carcasse (2) est une tringle de type "tressé".- Tire according to one of claims 1 to 4, characterized in that the anchoring rod (1) of the carcass reinforcement (2) is a rod of the "braided" type.
- Pneumatique selon l'une des revendications 1 à 5, caractérisé en ce que les éléments de renforcement de l'armature (6) de renforcement sont des tronçons ou des ensembles de tronçons de câbles, de longueur circonférentielle comprise entre 0,2 et 0,4 fois la longueur circonférentielle moyenne de l'armature, mesurée à la pose sur le tambour de confection de l'ébauche de carcasse.- Tire according to one of claims 1 to 5, characterized in that the reinforcing elements of the reinforcing armature (6) are sections or sets of cable sections, of circumferential length between 0.2 and 0 , 4 times the average circumferential length of the reinforcement, measured when it is laid on the drum for making the carcass blank.
- Pneumatique selon la revendication 6, caractérisé en ce que les interstices ou coupures circonférentielles entre tronçons coupés étant décalés les uns par rapport aux autres. - A tire according to claim 6, characterized in that the interstices or circumferential cuts between cut sections being offset with respect to each other.
EP98966633A 1998-01-12 1998-12-16 Tyre bead with reinforcing circumferential elements Expired - Lifetime EP1047567B1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
FR9800290A FR2773517B1 (en) 1998-01-12 1998-01-12 TIRE SADDLE WITH CIRCUMFERENTIAL REINFORCEMENT ELEMENTS
FR9800290 1998-01-12
PCT/EP1998/008263 WO1999034991A1 (en) 1998-01-12 1998-12-16 Tyre bead with reinforcing circumferential elements

Publications (2)

Publication Number Publication Date
EP1047567A1 true EP1047567A1 (en) 2000-11-02
EP1047567B1 EP1047567B1 (en) 2002-12-11

Family

ID=9521738

Family Applications (1)

Application Number Title Priority Date Filing Date
EP98966633A Expired - Lifetime EP1047567B1 (en) 1998-01-12 1998-12-16 Tyre bead with reinforcing circumferential elements

Country Status (12)

Country Link
US (1) US6443204B1 (en)
EP (1) EP1047567B1 (en)
JP (1) JP4557423B2 (en)
KR (1) KR100639523B1 (en)
CN (1) CN1149155C (en)
BR (1) BR9814585A (en)
CA (1) CA2318334C (en)
DE (1) DE69810161T2 (en)
ES (1) ES2188042T3 (en)
FR (1) FR2773517B1 (en)
RU (1) RU2219074C2 (en)
WO (1) WO1999034991A1 (en)

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002019430A (en) * 2000-07-05 2002-01-23 Bridgestone Corp Pneumatic tire
FR2840562B1 (en) * 2002-06-10 2004-07-23 Michelin Soc Tech TIRE BUCKLE FRAME INCLUDING DISCONTINUOUS REINFORCEMENTS
JP5048677B2 (en) * 2006-10-20 2012-10-17 株式会社ブリヂストン Pneumatic tire
ES2382306T3 (en) * 2006-10-20 2012-06-07 Bridgestone Corporation Tire
JP4703583B2 (en) * 2007-02-06 2011-06-15 株式会社ブリヂストン Pneumatic tire
FR2953457B1 (en) * 2009-12-03 2011-12-09 Michelin Soc Tech PNEUMATIC HAVING AN IMPROVED BOURRELET
JP2013100062A (en) * 2011-11-09 2013-05-23 Bridgestone Corp Pneumatic tire
FR2987312B1 (en) * 2012-02-28 2014-03-14 Michelin & Cie PNEUMATIC HAVING AN IMPROVED BOURRELET.
WO2017074335A1 (en) * 2015-10-28 2017-05-04 Compagnie Generale Des Etablissements Michelin Hybrid bead cores for tires
CN111559208A (en) * 2020-04-14 2020-08-21 安徽佳通乘用子午线轮胎有限公司 Special inflatable radial tire for overtravel race

Family Cites Families (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR750726A (en) 1932-05-14 1933-08-17 Michelin & Cie Improvements to casing frames for pneumatic tires
NL95227C (en) 1957-03-14 Michelin & Cie
FR1234995A (en) 1958-09-05 1960-07-01 Dunlop Sa Improvements to pneumatic tires
FR1256432A (en) 1959-05-08 1961-03-17 Dunlop Sa Improvements to pneumatic envelopes
FR2055988A5 (en) 1969-08-14 1971-05-14 Dunlop Ltd
DE2901719A1 (en) 1978-01-20 1979-07-26 Michelin & Cie VEHICLE AIR TIRES
FR2415016A1 (en) 1978-01-20 1979-08-17 Michelin & Cie Partially concave sidewall profiles for tubeless tyres - to enhance radial flexibility and hench ride comfort
JPS5934521B2 (en) 1980-06-09 1984-08-23 株式会社ブリヂストン Radial tire for heavy loads
JPS57191104A (en) * 1981-05-17 1982-11-24 Toyo Tire & Rubber Co Ltd Radial tire for truck and bus
JPS59109406A (en) * 1982-12-14 1984-06-25 Yokohama Rubber Co Ltd:The Pneumatic radial tyre for heavy load
JPS59216709A (en) * 1983-05-24 1984-12-06 Bridgestone Corp Radial tire excellent in durability for bead part
FR2601293B1 (en) * 1986-07-09 1988-11-18 Michelin & Cie SHEATHED PIPE FOR TIRE COVERS; PROCESS FOR MAKING THIS TRINGLE; TIRE ENCLOSURES COMPRISING THIS TRINGLE.
JPS638006A (en) * 1986-06-30 1988-01-13 Yokohama Rubber Co Ltd:The Radial tyre for small truck
US5181978A (en) 1989-11-25 1993-01-26 Sumitomo Rubber Industries, Ltd. Tire and rim assembly with the tire having 15 degree taper bead parts
JPH03189214A (en) * 1989-12-18 1991-08-19 Toyo Tire & Rubber Co Ltd Pneumatic radial tire for heavy duty service
JP2682902B2 (en) * 1991-02-15 1997-11-26 住友ゴム工業株式会社 Tubeless radial tires for heavy loads
JPH05155205A (en) * 1991-12-04 1993-06-22 Bridgestone Corp Pneumatic tire for heavy load
FR2718390A1 (en) * 1994-04-11 1995-10-13 Michelin & Cie Pneumatic with reinforced sidewalls.
FR2730190B1 (en) * 1995-02-02 1997-04-18 Michelin & Cie TIRE SADDLES
FR2734764A1 (en) * 1995-05-30 1996-12-06 Michelin & Cie TIRE WITH A REINFORCING TAPE WITH CIRCUMFERENTIAL ELEMENTS.

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO9934991A1 *

Also Published As

Publication number Publication date
CA2318334A1 (en) 1999-07-15
JP4557423B2 (en) 2010-10-06
FR2773517A1 (en) 1999-07-16
JP2002500123A (en) 2002-01-08
ES2188042T3 (en) 2003-06-16
FR2773517B1 (en) 2000-02-04
KR20010034033A (en) 2001-04-25
CN1284917A (en) 2001-02-21
EP1047567B1 (en) 2002-12-11
DE69810161D1 (en) 2003-01-23
WO1999034991A1 (en) 1999-07-15
CA2318334C (en) 2004-02-10
CN1149155C (en) 2004-05-12
US6443204B1 (en) 2002-09-03
KR100639523B1 (en) 2006-10-31
RU2219074C2 (en) 2003-12-20
DE69810161T2 (en) 2003-10-09
BR9814585A (en) 2000-10-24

Similar Documents

Publication Publication Date Title
EP1084047B1 (en) Radial tyre reinforced tyre bead
EP1064159B1 (en) Radial tyre reinforced bead
CA2318333C (en) Tyre bead with circumferential reinforcing elements
EP1028858A1 (en) Crown ply reinforcement for heavy vehicle tyre
EP1098781B1 (en) Reinforced radial tyre bead
EP1047566B1 (en) Tyre bead with circumferential reinforcing elements
EP3484726A1 (en) Tyre with a reduced-weight bead region
EP1077815B1 (en) Radial tyre breaker ply reinforcement
WO2017191421A1 (en) Tyre with a reduced-weight bead region
EP1047567B1 (en) Tyre bead with reinforcing circumferential elements
FR2804907A1 (en) PNEUMATIC BOURRELET WITH TEXTILE NAPPES
EP0756950B1 (en) Tyre with reinforced beads
EP0724973B1 (en) Tyre bead
WO2018011512A1 (en) Tyre with a reduced-weight bead region
EP1077814B1 (en) Tyre breaker ply reinforcement
WO2002057096A1 (en) Tyre with additional ring
EP1011992A1 (en) Top reinforcement for tyre
WO2001058705A1 (en) Tyre bead
EP1648716B1 (en) Tyre for heavy vehicles
WO2017191422A1 (en) Tyre with a reduced-weight bead region
FR3068301A1 (en) PNEUMATIC WITH BOURRELET'S ZONE IS ALLEGEE

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20000814

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): DE ES FR GB IT SE

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

17Q First examination report despatched

Effective date: 20020228

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): DE ES FR GB IT SE

REG Reference to a national code

Ref country code: GB

Ref legal event code: FG4D

Free format text: NOT ENGLISH

REF Corresponds to:

Ref document number: 69810161

Country of ref document: DE

Date of ref document: 20030123

REG Reference to a national code

Ref country code: SE

Ref legal event code: TRGR

GBT Gb: translation of ep patent filed (gb section 77(6)(a)/1977)

Effective date: 20030414

REG Reference to a national code

Ref country code: ES

Ref legal event code: FG2A

Ref document number: 2188042

Country of ref document: ES

Kind code of ref document: T3

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed

Effective date: 20030912

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: SE

Payment date: 20081212

Year of fee payment: 11

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20081216

Year of fee payment: 11

EUG Se: european patent has lapsed
GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20091216

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20091216

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20091217

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: ES

Payment date: 20101223

Year of fee payment: 13

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: IT

Payment date: 20121227

Year of fee payment: 15

REG Reference to a national code

Ref country code: ES

Ref legal event code: FD2A

Effective date: 20130703

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: ES

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20111217

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20131231

REG Reference to a national code

Ref country code: FR

Ref legal event code: PLFP

Year of fee payment: 18

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20151211

Year of fee payment: 18

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20151221

Year of fee payment: 18

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20131216

REG Reference to a national code

Ref country code: DE

Ref legal event code: R119

Ref document number: 69810161

Country of ref document: DE

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

Effective date: 20170831

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20170102

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20170701